Malicious PDF — malware analysis report

Static analysis result for SHA-256 277c80b3e7c96276…

MALICIOUS

PDF

84.5 KB Created: 2021-08-29 13:31:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 6e887252790b3c00eb7afbfc0f280b35 SHA-1: c00359e1f63d6a88b274e7188657b032b102f0dd SHA-256: 277c80b3e7c96276e5ed5a685ebd981d0b207d4eb81e34d0a43d3532005c2637
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to websites that appear to be compromised CMS upload directories, a common tactic for hosting malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure and embedded URLs suggest it functions as a link farm to lure victims to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/4123a607b2ecbd1d89bac9b88d2801ec/64145650041.pdf In PDF document text
    • http://gzcil.com/uploadfile/files/xuseleketet.pdfIn PDF document text
    • http://waltwhitmanclassof1965.com/clients/c/cc/ccbfa8a87e297cd67510599b8aebcb74/File/sarizuxitonowekaxamedijo.pdfIn PDF document text
    • http://mentaplywood.com/images_upload/files/wodazuvapujavavotediboki.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/59433627244.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078c35669b12---50919615594.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/41734657719.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/92200012967.pdfIn PDF document text
    • https://shiokerbau1.com/contents//files/vuribi.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607256a05fb20---41627986890.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/64755bd10ba261929461fabb242fe021/sarola.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///xifik.pdfIn PDF document text
    • http://unseretochter.com/images/file/52219415218.pdfIn PDF document text
    • https://birudongker.com/contents//files/27788656574.pdfIn PDF document text
    • http://hanasushi6.com/uploads/files/20465557440.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae44cf8bf22---godudojoj.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/hj8rm9gdqntdiob4527rnf51a2/68441075667.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdba49a72a2---subuxoxa.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a3476754424---22024270018.pdfIn PDF document text
    • https://abeess.com/userfiles/file/64559096313.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/44123665346.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d86b287f8c---gijanizelifisagiwunimedi.pdfIn PDF document text
    • https://dnm.tw/uploads/files/202108220211557965.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/posigifenigi.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/fiperixepimane.pdfIn PDF document text
    • http://broeinest.org/ckfinder/userfiles/files/bewuvon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=prophecy+poe+5+linkPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e663.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE663 10384 bytes
SHA-256: ef636a956c36eff3d5b78e519a3a6f8578047efa11cae9dd49ccc79b8712d759
font_01_sfnt_off0000fdc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC2 17664 bytes
SHA-256: 2bc1527ea7d35fa125a37beb031db5c632f86258b5e3c3dff0325cdca14542f2
font_02_sfnt_off00012b22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1